Hi
I’ve been making a load of things (mostly rings) with either epoxy and/or PU resin. Some clear with inclusions and some opaque and some a mixture of the two. My questions concern the finishing of them. I understand epoxy resin isn’t UV resistant so clear would yellow over a period of time. Also, I find that I don’t always get the best finish when using silicone moulds. Therefore I need to coat each piece with a clear coat or a lacquer. I’ve had a look on EC website and forum and have found several possibilities. But which one would be best for my purpose?

1. A resin clear coat. Would I sand the piece then apply this to one side, let this dry then apply to the other side? Can it be painted on without brush marks? Can I then buff it on a buffing wheel?

2. GC50. Does this work on the same principle as a resin clear coat as above? Again would I apply it in sections, can it be painted on without brush marks and can it be buffed on a wheel?

3. I’ve also read on here about a 2 part clear lacquer used on cars. Is this just a general acrylic or is there a specific one that I should be looking for? What does the ‘2 part’ refer to? Would it bond ok with PU and epoxy?

Basically, im looking for the best method for UV protecting as well as achieving a high gloss finish on small jewellery pieces? I know some puritans out there may well suggest going through the sandpaper grits but I’ve tried this and it takes far too long with only barely adequate results?!

Hoping someone can point me in the right direction. Much appreciated. X

+x

 

oekmont - 12/27/2017 11:01:17 AM

1. Ec got a coating epoxy, wich should suit you needs. Best way to get it really even would be to spray paint it. But wiping it on with micro fibre cloth can give good results, too. This resin should be uv resistant.

2. This isn't made for coating applications. I don't know if it will do well in this case. Usually polyester doesn't stick well to epoxy. at least, gc 50 should cure tack free, unlike usual polyester.

3. 2 part means, that you have to mix two components together before you apply the laquer. 2 component lacquer is far more durable and chemically  resistant than any 1 component (rattle can) laquer. The uv resistance and gloss propertys should be at least as good as the epoxy coating resin, if not better.

You could buy uv blocker additive for epoxy resins. If you could get a good finish from the mould, you would not need any surface treatment.

Thanks so much for the response Oekmont. I will try the coating epoxy with a microfiber cloth as you suggest. I'm assuming it will be a bit thicker than normal resin so it will not 'pool' on the surface. Do I need to sand the piece first in order for it to grip?
I also read on here about a new casting epoxy that EC have been working on and are planning on releasing in January. Does anyone have an approximate due date?
I wish I could just buy a UV additive for my existing resin but alas some of my moulds have got several tiny scratches on them - is there a way to get rid of them and re-gloss the surface of silicone does anyone know?